ENVIRONMENT; As Aid Is Reduced, the Rodent Problem Explodes in Urban Areas

Henry Jones, an exterminator for the Camden County Health Department, could smell the rats as soon as he entered the dilapidated East Camden row house on Wednesday morning.

A breathtaking, acrid odor, something like a combination of urine and rotten food. Mr. Jones followed the stench through the darkened living room, where a young woman sat nursing a 2-week-old infant, to the kitchen, where the linoleum floor was worn away in large, damp patches and the sink brimmed with dishes clotted with a white, pasty batter. There, behind the stove, which was thickly crusted with burned food and aluminum foil, lay a large, dead rat, killed by poison left by Mr. Jones and his rodent control team a week before.

Nyesha Cherry, who rents the house on North 22d Street with the young mother, who is her sister, and their three brothers, told the men she had found four other dead rats ''the size of kittens'' in the kitchen during the past week. Her landlord had ignored her complaints of scrabbling noises, chewed clothing, rodent droppings and finally a live rat in the dining room. So she called the county health department.

''Somebody has got to get the rats out of here,'' she said.

The four-member Camden County Rodent Control team is the last line of defense for the residents of Camden and 57 surrounding municipalities. From Monday to Friday they respond to a never-ending supply of agitated callers. The complaints are just as likely to come from wealthy suburbs like Cherry Hill and Pennsauken, where bird feeders and restaurant dumpsters provide food for the ubiquitous scavengers. With complaints growing each year, the officers know they are fighting a losing battle.

It was not always this way. In the early 1970's, Federal assistance allowed Camden to hire 20 health education workers who conducted door-to-door inspections, lectured in schools and day-care centers and organized block-cleaning awards. The idea was to teach residents how to prevent rat infestations by keeping food and garbage tightly sealed and repairing cracks and broken windows where rodents enter homes. Poisoning is a last resort, Mr. Jones said. Rats always rebound where there is food and shelter, often in greater numbers.

''Sanitation and education is what keeps the rats down in the long term,'' he said. ''The killing of rats is always the last thing. But now it's just the killing, and education as far as we can.''

In the 1970's and early 1980's, the Federal Government gave New Jersey as much as $2 million a year for urban rodent control programs. But the aid ended in the early 1980's, when the responsibility for rodent control was transferred from the United States Public Health Service to the Department of Agriculture. Since 1993, New Jersey has spent only $177,000 a year for rodent control programs in four cities: Camden, Paterson, Newark and Jersey City. The money comes from a Federal block grant for preventive health services, leaving rat control to compete with other priorities like childhood immunizations and hypertension screening, said David Adam, of the State Department of Health and Human Services.

But the rats pose a significant public health threat. As well as causing fear and revulsion, they carry bacterial diseases like salmonella and leptospirosis, which can cause illness and even death. Norway rats, most common in New Jersey, are host to disease-carrying ticks and fleas. They also cause economic damage like house fires by gnawing through electrical cables

Rats can survive on almost any food, including waste in sewers, and they need only a half-inch crack to enter any dwelling, where they scurry along the walls, urinating and defecating more than 100 times a day. But surprisingly little is known about the extent of the damage they cause. Bruce A. Colvin, an environmental consultant and rat expert, said there is currently not a single Federal or academic study into the habits of urban rats in the United States, although there are thought to be as many rats as people. He said their numbers seem to be increasing even as state and Federal assistance to eliminate them decreases, but there is little scientific data to prove it.

''The vast majority of the public has just been left to fend for itself,'' Mr. Colvin said. ''This is really a national issue and it is an issue of national shame.''

Camden's $500,000-a-year program, financed mainly by county taxpayers, is one of the best in the state. Many cities, including Atlantic City, East Orange, Passaic and Plainfield, do not even have rodent control units. Homeowners and municipalities must hire private pest control companies, which tend to focus on extermination rather than prevention, Mr. Adam said.

Paterson's program was so poorly financed that it stopped for several years, resuming only last year. The hiatus prompted Assemblywoman Nellie Poe, a Democrat, to ask the State Legislature to spend an extra $336,000 for rat control in the four cities this year. The bill was approved by the Assembly Health Committee on Jan. 21 and now heads to the Assembly Appropriations Committee for consideration.

But the Assemblywoman acknowledged that even the additional aid was not enough.

''I am sure that if research is done we would come upon other areas that are in just as much need,'' she said. ''But this is a step in the right direction.''

The Camden team will probably continue to spend most days visiting the sites of known rat infestation, where Miguel Nunez, an exterminator, drops plastic bags filled with Telon, a bright blue-green poison pellet, into rat holes. The characteristic burrows are about the circumference of a baseball, often capped with soggy layers of garbage.

On Morton Street in the Whitman Park section, the holes were at the grassy edge of a badly cracked sidewalk littered with glistening plastic wrappers and wet cardboard. Nearby, a vacant lot between two narrow houses was piled high with brush and garbage: plastic juice bottles, candy wrappers, sheets of green felt and a jar of creamy pesto sauce. The unmistakable smell of rats lingered in the air. ''It is certainly going to get worse if they don't curtail it,'' said Ralph Green, the principal sanitarian for Camden County. ''It should be more preventative. They need to put more resources into it. We've become reactionary now.''